/**
* author Remy Sharp
* url http://remysharp.com/tag/marquee
*/

(function($) {

    var ua = $.browser;
    if (ua.mozilla) {
        $.fn.marquee = function(klass) {

            var newMarquee = [],
            last = this.length;

            // works out the left or right hand reset position, based on scroll
            // behavior, current direction and new direction
            function getReset(newDir, marqueeRedux, marqueeState) {
                var behavior = marqueeState.behavior, width = marqueeState.width, dir = marqueeState.dir;
                var r = 0;
                if (behavior == 'alternate') {
                    r = newDir == 1 ? marqueeRedux[marqueeState.widthAxis] - (width * 2) : width;
                } else if (behavior == 'slide') {
                    if (newDir == -1) {
                        r = dir == -1 ? marqueeRedux[marqueeState.widthAxis] : width;
                    } else {
                        r = dir == -1 ? marqueeRedux[marqueeState.widthAxis] - (width * 2) : 0;
                    }
                } else {
                    r = newDir == -1 ? marqueeRedux[marqueeState.widthAxis] : 0;
                }
                return r;
            }

            // single "thread" animation
            function animateMarquee() {
                var i = newMarquee.length,
                marqueeRedux = null,
                $marqueeRedux = null,
                marqueeState = {},
                newMarqueeList = [],
                hitedge = false;

                while (i--) {
                    marqueeRedux = newMarquee[i];
                    $marqueeRedux = $(marqueeRedux);
                    marqueeState = $marqueeRedux.data('marqueeState');

                    if ($marqueeRedux.data('paused') !== true) {
                        // TODO read scrollamount, dir, behavior, loops and last from data
                        marqueeRedux[marqueeState.axis] += (marqueeState.scrollamount * marqueeState.dir);

                        // only true if it's hit the end
                        hitedge = marqueeState.dir == -1 ? marqueeRedux[marqueeState.axis] <= getReset(marqueeState.dir * -1, marqueeRedux, marqueeState) : marqueeRedux[marqueeState.axis] >= getReset(marqueeState.dir * -1, marqueeRedux, marqueeState);

                        if ((marqueeState.behavior == 'scroll' && marqueeState.last == marqueeRedux[marqueeState.axis]) || (marqueeState.behavior == 'alternate' && hitedge && marqueeState.last != -1) || (marqueeState.behavior == 'slide' && hitedge && marqueeState.last != -1)) {
                            if (marqueeState.behavior == 'alternate') {
                                marqueeState.dir *= -1; // flip
                            }
                            marqueeState.last = -1;

                            $marqueeRedux.trigger('stop');

                            marqueeState.loops--;
                            if (marqueeState.loops === 0) {
                                if (marqueeState.behavior != 'slide') {
                                    marqueeRedux[marqueeState.axis] = getReset(marqueeState.dir, marqueeRedux, marqueeState);
                                } else {
                                    // corrects the position
                                    marqueeRedux[marqueeState.axis] = getReset(marqueeState.dir * -1, marqueeRedux, marqueeState);
                                }

                                $marqueeRedux.trigger('end');
                            } else {
                                // keep this marquee going
                                newMarqueeList.push(marqueeRedux);
                                $marqueeRedux.trigger('start');
                                marqueeRedux[marqueeState.axis] = getReset(marqueeState.dir, marqueeRedux, marqueeState);
                            }
                        } else {
                            newMarqueeList.push(marqueeRedux);
                        }
                        marqueeState.last = marqueeRedux[marqueeState.axis];

                        // store updated state only if we ran an animation
                        $marqueeRedux.data('marqueeState', marqueeState);
                    } else {
                        // even though it's paused, keep it in the list
                        newMarqueeList.push(marqueeRedux);
                    }
                }

                newMarquee = newMarqueeList;

                if (newMarquee.length) {
                    setTimeout(animateMarquee, 25);
                }
            }

            // TODO consider whether using .html() in the wrapping process could lead to loosing predefined events...
            this.each(function(i) {
                var $marquee = $(this),
                width = $marquee.attr('width') || $marquee.width(),
                height = $marquee.attr('height') || $marquee.height(),
                $marqueeRedux = $marquee.after('<div ' + (klass ? 'class="' + klass + '" ' : '') + 'style="display: block-inline; width: ' + width + 'px; height: ' + height + 'px; overflow: hidden;"><div style="float: left; white-space: nowrap;">' + $marquee.html() + '</div></div>').next(),
                marqueeRedux = $marqueeRedux.get(0),
                hitedge = 0,
                direction = ($marquee.attr('direction') || 'left').toLowerCase(),
                marqueeState = {
                    dir: /down|right/.test(direction) ? -1 : 1,
                    axis: /left|right/.test(direction) ? 'scrollLeft' : 'scrollTop',
                    widthAxis: /left|right/.test(direction) ? 'scrollWidth' : 'scrollHeight',
                    last: -1,
                    loops: $marquee.attr('loop') || -1,
                    scrollamount: $marquee.attr('scrollamount') || this.scrollAmount || 2,
                    behavior: ($marquee.attr('behavior') || 'scroll').toLowerCase(),
                    width: /left|right/.test(direction) ? width : height
                };

                // corrects a bug in Firefox - the default loops for slide is -1
                if ($marquee.attr('loop') == -1 && marqueeState.behavior == 'slide') {
                    marqueeState.loops = 1;
                }

                $marquee.remove();

                // add padding
                if (/left|right/.test(direction)) {
                    $marqueeRedux.find('> div').css('padding', '0 ' + width + 'px');
                } else {
                    $marqueeRedux.find('> div').css('padding', height + 'px 0');
                }

                // events
                $marqueeRedux.bind('stop', function() {
                    $marqueeRedux.data('paused', true);
                }).bind('pause', function() {
                    $marqueeRedux.data('paused', true);
                }).bind('start', function() {
                    $marqueeRedux.data('paused', false);
                }).bind('unpause', function() {
                    $marqueeRedux.data('paused', false);
                }).data('marqueeState', marqueeState); // finally: store the state

                // todo - rerender event allowing us to do an ajax hit and redraw the marquee

                newMarquee.push(marqueeRedux);

                marqueeRedux[marqueeState.axis] = getReset(marqueeState.dir, marqueeRedux, marqueeState);
                $marqueeRedux.trigger('start');

                // on the very last marquee, trigger the animation
                if (i + 1 == last) {
                    animateMarquee();
                }
            });

            return $(newMarquee);
        };
    }
} (jQuery));